Springboot java后台生成图片验证码

验证码工具类

public class ValidateImgCode {

    private static final Logger logger = LoggerFactory.getLogger(ValidateImgCode.class);

    public static final String[] strArr = {"3", "4", "5", "6", "7", "8", "9", "A", "B", "C", "D", "E", "F", "G", "H", "J", "K", "M", "N", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y"};

    public static String randomCodeKey = "imgCode";
    public static boolean caseInsensitive = true;
    public static int img_width = 65;
    public static int img_height = 20;
    public static int img_randNumber = 4;
    @Autowired
    private JRedisClient jRedisClient;

    public String render(HttpServletRequest request,HttpServletResponse response) throws Exception{
        BufferedImage image = new BufferedImage(img_width, img_height, BufferedImage.TYPE_INT_RGB);
        String vCode = drawGraphic(image);
        response.setHeader("Pragma","no-cache");
        response.setHeader("Cache-Control","no-cache");
        response.setDateHeader("Expires", 0);
        response.setContentType("image/jpeg");
        //request.getSession().setAttribute(randomCodeKey, vCode);//将验证码放入session,校验时比对
        jRedisClient.addCacheString(randomCodeKey,vCode,60*5);//将验证码放入redis,校验时比对

        OutputStream sos = null;
        try {
            sos = response.getOutputStream();
            ImageIO.write(image, "jpeg",sos);
        } catch (Exception e) {
            throw new RuntimeException(e);
        } finally {
            if (sos != null) {
                try {
                    sos.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return null;
    }

    /**
     * 生成图片验证码
     * */
    private String drawGraphic(BufferedImage image){
        // 获取图形上下文
        Graphics g = image.createGraphics();
        // 生成随机类
        Random random = new Random();
        // 设定背景色
        g.setColor(getRandColor(200, 250));
        g.fillRect(0, 0, img_width, img_height);
        // 设定字体
        g.setFont(new Font("Times New Roman", Font.PLAIN, 18));

        // 随机产生155条干扰线，使图象中的认证码不易被其它程序探测到
        g.setColor(getRandColor(160, 200));
        for (int i = 0; i < 155; i++) {
            int x = random.nextInt(img_width);
            int y = random.nextInt(img_height);
            int xl = random.nextInt(12);
            int yl = random.nextInt(12);
            g.drawLine(x, y, x + xl, y + yl);
        }

        // 取随机产生的认证码(img_randNumber位数字)
        String sRand = "";
        for (int i = 0; i < img_randNumber; i++) {
            String rand = String.valueOf(strArr[random.nextInt(strArr.length)]);
            sRand += rand;
            // 将认证码显示到图象中
            g.setColor(new Color(20 + random.nextInt(110), 20 + random.nextInt(110), 20 + random.nextInt(110)));
            // 调用函数出来的颜色相同，可能是因为种子太接近，所以只能直接生成
            g.drawString(rand, 13 * i + 6, 16);
        }
        // 图象生效
        g.dispose();
        return sRand;
    }

    /*
     * 给定范围获得随机颜色
     */
    private Color getRandColor(int fc, int bc) {
        Random random = new Random();
        if (fc > 255)
            fc = 255;
        if (bc > 255)
            bc = 255;
        int r = fc + random.nextInt(bc - fc);
        int g = fc + random.nextInt(bc - fc);
        int b = fc + random.nextInt(bc - fc);
        return new Color(r, g, b);
    }

}

controller层校验部分

ResultResponse respo = new ResultResponse <>();
try {
            //忽略英文字母大小写
            if (authCode.equalsIgnoreCase(jRedisClient.getCacheString(ValidateImgCode.randomCodeKey))) {
                respo.setCode("2");
                respo.setMessage("验证码正确");
                return respo;
            } else {
                respo.setCode("3");
                respo.setMessage("验证码错误");
                return respo;
            }
        }catch (Exception e){
           logger.error("校验验证码异常");
            respo.setCode("4");
            respo.setMessage("校验异常");
           return respo;
        }